Nicholeen M Viall

Nicholeen M Viall

  • 301.286.4054
  • NASA/GSFC
  • Mail Code: 671
  • Greenbelt , MD 20771
  • Employer: NASA
  • Research Interests

    Solar Wind Formation

    Investigating structures in the ambient solar wind as tracers of solar wind formation. We use remote imaging data and in situ measurements in the heliosphere.

    Solar Coronal Heating

    Researching active regions and quiet Sun plasmas by developing new analyses of the multi-wavelength Solar Dynamics Observatory/ Atmospheric Imaging Assembly (SDO/AIA) data. Use physics-based coronal flux tube models to understand coronal heating and for the interpretation of line-of-sight effects in coronal observations.

    Positions/Employment

    3/2012 - Present

    Research Astrophysicist

    NASA Goddard Space Flight Center, Greenblet, MD, USA  
    2010 - 2012

    NASA Postdoctoral Fellow

    Solar Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA  Investigation of coronal heating in active region loops using time series analysis, physics-based coronal loop models, and the multi-wavelength SDO/AIA data.
    2005 - 2009

    Graduate Research Assistant

    Department of Astronomy, Boston University, Boston, MA, USA Studied non-turbulent periodic density structures in the ambient solar wind, their affect on the Magnetosphere, focusing on the ULF wave response, and their possible source region and source mechanism. The main tools used were spectral analysis and time series analysis of Wind/Solar Wind Experiment data, Solar TErrestrial RElations Observatory/ Sun Earth Connection Coronal and Heliospheric Investigation white light images, and Geostationary Operational Environment Satellites magnetometer data.
    2004 - 2004

    Graduate Teaching Fellow

    Department of Astronomy, Boston University, Boston, MA, USA Responsible for teaching four Astronomy 202 lab sections per week; taught astronomy and space physics material complementary to main lectures; running laboratory experiments and discussion/office hours; grading homework assignments and lab reports. Attended bi-weekly class lectures and weekly teaching fellow class.

    Education

    Ph.D. in Astronomy, Boston University, Boston, MA, January, 2010
    "Periodic Solar Wind Density Structures"

    M.A. in Astronomy, Boston University, Boston, MA, May, 2007

    B.S. in Astronomy and Physics, Univrsity of Washington, Seattle, WA, June, 2004

    Professional Service

    American Geophysical Union (AGU)
        Space Physics and Aeronomy (SPA), outstanding student paper awards committee co-chair and member of AGU SPA executive council, August 2011-Feb 2013
        Outstanding student paper awards judge, Fall AGU meeting, 2009-present
        Co-organizer and session chair of Fall AGU SPA session titled ‘Comparing Models of the Solar Magnetic Field With Data’, 2011
        Lead organizer and session chair of Fall AGU SPA session titled ‘Recent Advances in Solar Coronal Heating’, 2012

    International 'Coronal Loops' Workshop
        Steering Committee member, May 2012-present
        Science Organizing Committee, 2013-present

    Goddard Space Flight Center
        New and Developing Professionals Advisory Committee, May 2011-present
        Taught introduction to solar/astronomy observational techniques course at the Goddard Space Flight Center Educator’s Workshop, July 2012
        Solar and space physics presentation at the Glenn Dale Elementary School Career Day, May 2012
        Solar and space weather presentation as part of The Girl Scouts of America 100th anniversary celebration, ‘The Scientist is In’ event, July 2012
        Served on the GSFC Science Panel for Summer Interns, August 2012

    NSF Solar, Heliospheric, and INterplanetary Environment program (SHINE)
        SHINE student representative, 2008 and 2009.
        Co-GEM-SHINE student day leader (GEM-SHINE 2008 meeting)
        Served as a reviewer on the SHINE National Science Foundation research proposals panel review

    Other
        Working group leader at the ‘Tracing the Connections of Eruptive Events’ workshop, Fall, 2012


    Professional Societies

    Women of Aerospace, 2013 - Present
    American Astronomical Society (AAS), 2010 - Present
    American Geophysical Union, 2005 - Present

    Awards

    Recipient of a NASA Early Career Achievement Medal, 2018

    Recipient of the 2018 American Astronomical Society (AAS)/Solar Physics Division (SPD) Karen Harvey Prize for a significant contribution to the study of the Sun early in a person's professional career. Awarded ‘for her fundamental contributions to understanding coronal heating and the slow solar wind, and for her valuable service to the science community and the general public.’

    Selected Publications

    Refereed

    Kepko, L., and N. M. Viall. 2019. "The Source, Significance, and Magnetospheric Impact of Periodic Density Structures Within Stream Interaction Regions." Journal of Geophysical Research: Space Physics, (In Press) [10.1029/2019ja026962]

    Barnes, W. T., S. J. Bradshaw, and N. M. Viall. 2019. "Understanding Heating in Active Region Cores through Machine Learning. I. Numerical Modeling and Predicted Observables." The Astrophysical Journal, 880 (1): 56 [10.3847/1538-4357/ab290c]

    Mason, E. I., S. K. Antiochos, and N. M. Viall. 2019. "Observations of Solar Coronal Rain in Null Point Topologies." The Astrophysical Journal Letters, 874 (2): L33 [10.3847/2041-8213/ab0c5d]

    Di Matteo, S., N. M. Viall, L. Kepko, et al. S. Wallace, C. N. Arge, and P. MacNeice. 2019. "Helios Observations of Quasiperiodic Density Structures in the Slow Solar Wind at 0.3, 0.4, and 0.6 AU." Journal of Geophysical Research: Space Physics, 124 (2): 837-860 [10.1029/2018ja026182]

    DeForest, C. E., R. A. Howard, M. Velli, N. Viall, and A. Vourlidas. 2018. "The Highly Structured Outer Solar Corona." The Astrophysical Journal, 862 (1): 18 [10.3847/1538-4357/aac8e3]

    Nita, G. M., N. M. Viall, J. A. Klimchuk, et al. M. A. Loukitcheva, D. E. Gary, A. A. Kuznetsov, and G. D. Fleishman. 2018. "Dressing the Coronal Magnetic Extrapolations of Active Regions with a Parameterized Thermal Structure." The Astrophysical Journal, 853 (1): 66 [10.3847/1538-4357/aaa4bf]

    Strong, K., N. Viall, J. Schmelz, and J. Saba. 2017. "Understanding Space Weather: Part III: The Sun’s Domain." Bulletin of the American Meteorological Society, 98 (12): 2593-2602 [10.1175/bams-d-16-0204.1]

    Viall, N. M., and J. A. Klimchuk. 2017. "A Survey of Nanoflare Properties in Active Regions Observed with theSolar Dynamics Observatory." The Astrophysical Journal, 842 (2): 108 [10.3847/1538-4357/aa7137]

    Viall, N. M., and J. A. Klimchuk. 2016. "SIGNATURES OF STEADY HEATING IN TIME LAG ANALYSIS OF CORONAL EMISSION." The Astrophysical Journal, 828 (2): 76 [10.3847/0004-637x/828/2/76]

    DeForest, C. E., W. H. Matthaeus, N. M. Viall, and S. R. Cranmer. 2016. "FADING CORONAL STRUCTURE AND THE ONSET OF TURBULENCE IN THE YOUNG SOLAR WIND." The Astrophysical Journal, 828 (2): 66 [10.3847/0004-637x/828/2/66]

    Kepko, L., N. Viall, S. K. Antiochos, et al. S. T. Lepri, J. C. Kasper, and M. Weberg. 2016. "Implications of L1 observations for slow solar wind formation by solar reconnection." Geophysical Research Letters, 43 (9): 4089–4097 [10.1002/2016gl068607]

    Bradshaw, S. J., and N. M. Viall. 2016. "PATTERNS OF ACTIVITY IN A GLOBAL MODEL OF A SOLAR ACTIVE REGION." The Astrophysical Journal, 821 (1): 63 [10.3847/0004-637x/821/1/63]

    Viall, N. M., and A. Vourlidas. 2015. "PERIODIC DENSITY STRUCTURES AND THE ORIGIN OF THE SLOW SOLAR WIND." The Astrophysical Journal, 807 (2): 176 [10.1088/0004-637x/807/2/176]

    Viall, N. M., and J. A. Klimchuk. 2015. "THE TRANSITION REGION RESPONSE TO A CORONAL NANOFLARE: FORWARD MODELING AND OBSERVATIONS INSDO/AIA." The Astrophysical Journal, 799 (1): 58 [10.1088/0004-637x/799/1/58]

    Hartinger, M. D., D. Welling, N. M. Viall, M. B. Moldwin, and A. Ridley. 2014. "The effect of magnetopause motion on fast mode resonance." Journal of Geophysical Research: Space Physics, 119 (10): 8212-8227 [10.1002/2014ja020401]

    Uritskiy, V. M., J. M. Davila, N. M. Viall-Kepko, and L. Ofman. 2013. "MEASURING TEMPERATURE-DEPENDENT PROPAGATING DISTURBANCES IN CORONAL FAN LOOPS USING MULTIPLE SDO/AIA CHANNELS AND THE SURFING TRANSFORM TECHNIQUE." ASTROPHYSICAL JOURNAL, 778: [10.1088/0004-637X/778/1/26]

    Viall, N. M., and J. A. Klimchuk. 2013. "Modeling the Line-of-Sight Integrated Emission in the Corona: Implications for Coronal Heating." The Astrophysical Journal, 771 (2): 115 [10.1088/0004-637X/771/2/115]

    Viall, N., and J. Klimchuk. 2012. "Nanoflare Properties throughout Active Regions: Comparing SDO/AIA Observations with Modeled Active Region Light Curves." American Astronomical Society Meeting Abstracts #220, 220: #309.04-.

    Viall, N., and J. Klimchuk. 2011. "Patterns of Nanoflare Heating Exhibited by Active Regions Observed with SDO/AIA." Bulletin of the American Astronomical Society, 2103-:

    Viall, N. M., H. E. Spence, A. Vourlidas, and R. Howard. 2010. "Examining Periodic Solar-Wind Density Structures Observed in the SECCHI Heliospheric Imagers." Solar Physics, 261 (175): [10.1007/s11207-010-9633-1]

    Viall, N. M., H. E. Spence, and J. Kasper. 2009. "Are periodic solar wind number density structures formed in the solar corona?" Geophysical Research Letters, 36 (23): L23102 [10.1029/2009GL041191]

    Viall, N. M., E. L. Kepko, and H. E. Spence. 2009. "Relative occurrence rates and connection of discrete frequency oscillations in the solar wind density and dayside magnetosphere." J. Geophys. Res., 114 (A01201): [10.1029/2008JA013334]

    Viall, N. M., L. Kepko, and H. E. Spence. 2008. "Inherent length-scales of periodic solar wind number density structures." Journal of Geophysical Research (Space Physics), 113: [7101 10.1029/2007JA012881]

    Selected Publications

    Refereed

    Kepko, L., and N. M. Viall. 2019. "The Source, Significance, and Magnetospheric Impact of Periodic Density Structures Within Stream Interaction Regions." Journal of Geophysical Research: Space Physics (In Press) [10.1029/2019ja026962]

    Barnes, W. T., S. J. Bradshaw, and N. M. Viall. 2019. "Understanding Heating in Active Region Cores through Machine Learning. I. Numerical Modeling and Predicted Observables." The Astrophysical Journal 880 (1): 56 [10.3847/1538-4357/ab290c]

    Mason, E. I., S. K. Antiochos, and N. M. Viall. 2019. "Observations of Solar Coronal Rain in Null Point Topologies." The Astrophysical Journal Letters 874 (2): L33 [10.3847/2041-8213/ab0c5d]

    Di Matteo, S., N. M. Viall, L. Kepko, et al. S. Wallace, C. N. Arge, and P. MacNeice. 2019. "Helios Observations of Quasiperiodic Density Structures in the Slow Solar Wind at 0.3, 0.4, and 0.6 AU." Journal of Geophysical Research: Space Physics 124 (2): 837-860 [10.1029/2018ja026182]

    DeForest, C. E., R. A. Howard, M. Velli, N. Viall, and A. Vourlidas. 2018. "The Highly Structured Outer Solar Corona." The Astrophysical Journal 862 (1): 18 [10.3847/1538-4357/aac8e3]

    Nita, G. M., N. M. Viall, J. A. Klimchuk, et al. M. A. Loukitcheva, D. E. Gary, A. A. Kuznetsov, and G. D. Fleishman. 2018. "Dressing the Coronal Magnetic Extrapolations of Active Regions with a Parameterized Thermal Structure." The Astrophysical Journal 853 (1): 66 [10.3847/1538-4357/aaa4bf]

    Strong, K., N. Viall, J. Schmelz, and J. Saba. 2017. "Understanding Space Weather: Part III: The Sun’s Domain." Bulletin of the American Meteorological Society 98 (12): 2593-2602 [10.1175/bams-d-16-0204.1]

    Viall, N. M., and J. A. Klimchuk. 2017. "A Survey of Nanoflare Properties in Active Regions Observed with theSolar Dynamics Observatory." The Astrophysical Journal 842 (2): 108 [10.3847/1538-4357/aa7137]

    Viall, N. M., and J. A. Klimchuk. 2016. "SIGNATURES OF STEADY HEATING IN TIME LAG ANALYSIS OF CORONAL EMISSION." The Astrophysical Journal 828 (2): 76 [10.3847/0004-637x/828/2/76]

    DeForest, C. E., W. H. Matthaeus, N. M. Viall, and S. R. Cranmer. 2016. "FADING CORONAL STRUCTURE AND THE ONSET OF TURBULENCE IN THE YOUNG SOLAR WIND." The Astrophysical Journal 828 (2): 66 [10.3847/0004-637x/828/2/66]

    Kepko, L., N. Viall, S. K. Antiochos, et al. S. T. Lepri, J. C. Kasper, and M. Weberg. 2016. "Implications of L1 observations for slow solar wind formation by solar reconnection." Geophysical Research Letters 43 (9): 4089–4097 [10.1002/2016gl068607]

    Bradshaw, S. J., and N. M. Viall. 2016. "PATTERNS OF ACTIVITY IN A GLOBAL MODEL OF A SOLAR ACTIVE REGION." The Astrophysical Journal 821 (1): 63 [10.3847/0004-637x/821/1/63]

    Viall, N. M., and A. Vourlidas. 2015. "PERIODIC DENSITY STRUCTURES AND THE ORIGIN OF THE SLOW SOLAR WIND." The Astrophysical Journal 807 (2): 176 [10.1088/0004-637x/807/2/176]

    Viall, N. M., and J. A. Klimchuk. 2015. "THE TRANSITION REGION RESPONSE TO A CORONAL NANOFLARE: FORWARD MODELING AND OBSERVATIONS INSDO/AIA." The Astrophysical Journal 799 (1): 58 [10.1088/0004-637x/799/1/58]

    Hartinger, M. D., D. Welling, N. M. Viall, M. B. Moldwin, and A. Ridley. 2014. "The effect of magnetopause motion on fast mode resonance." Journal of Geophysical Research: Space Physics 119 (10): 8212-8227 [10.1002/2014ja020401]

    Uritskiy, V. M., J. M. Davila, N. M. Viall-Kepko, and L. Ofman. 2013. "MEASURING TEMPERATURE-DEPENDENT PROPAGATING DISTURBANCES IN CORONAL FAN LOOPS USING MULTIPLE SDO/AIA CHANNELS AND THE SURFING TRANSFORM TECHNIQUE." ASTROPHYSICAL JOURNAL 778 [10.1088/0004-637X/778/1/26]

    Viall, N. M., and J. A. Klimchuk. 2013. "Modeling the Line-of-Sight Integrated Emission in the Corona: Implications for Coronal Heating." The Astrophysical Journal 771 (2): 115 [10.1088/0004-637X/771/2/115]

    Viall, N., and J. Klimchuk. 2012. "Nanoflare Properties throughout Active Regions: Comparing SDO/AIA Observations with Modeled Active Region Light Curves." American Astronomical Society Meeting Abstracts #220 220 #309.04-

    Viall, N., and J. Klimchuk. 2011. "Patterns of Nanoflare Heating Exhibited by Active Regions Observed with SDO/AIA." Bulletin of the American Astronomical Society 2103-

    Viall, N. M., H. E. Spence, A. Vourlidas, and R. Howard. 2010. "Examining Periodic Solar-Wind Density Structures Observed in the SECCHI Heliospheric Imagers." Solar Physics 261 (175): [10.1007/s11207-010-9633-1]

    Viall, N. M., H. E. Spence, and J. Kasper. 2009. "Are periodic solar wind number density structures formed in the solar corona?" Geophysical Research Letters 36 (23): L23102 [10.1029/2009GL041191]

    Viall, N. M., E. L. Kepko, and H. E. Spence. 2009. "Relative occurrence rates and connection of discrete frequency oscillations in the solar wind density and dayside magnetosphere." J. Geophys. Res. 114 (A01201): [10.1029/2008JA013334]

    Viall, N. M., L. Kepko, and H. E. Spence. 2008. "Inherent length-scales of periodic solar wind number density structures." Journal of Geophysical Research (Space Physics) 113 [7101 10.1029/2007JA012881]

                                                                                                                                                                                            
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